Daniel cook



(No Model.)

` H, F. PARSONS.

ROGKYDRILL. No. 250,385. Pat'entdyDeo. 6,1881.

Hun...

ATTORHEY? N. PETERS. Phuwlnhagmvher. wash; nnnnnnn c.

these holes with the. spirali enables the'spiral I ainaware that drills have been constructed heretofore which contained a spiral groove ertending upward on lthe drill-rod,for causing the discharge ofthe cuttings', which spiral groove is produced. by twisting the' drill; butsuoli groove is necessarily of too great a pitch to be of much use for discharging the drillings. By the use of the wire described herein a spiral is produced around the rod ot much less pitch than was' heretofore practicable, `and thus l ain able to greatly facilitate the discharge of the drillings. 0n a drill-rod three-quarters of an inch in diameter I prefer to give the spiral rib about one-halt iiicli pitch. y

Asstated above, I prefer to have a cuttinghead detachable from the drillrod, because it is obvious that by so doing I am enabled to produce an economy in the apparatus used, for as soon as one cutting-head becomes dull' or Worn, or 'unfit for Iuse,'I can rei/nove il'antl substitute therefor another cutting-head, and

thus one drill-rod will beiinade ro ansirer the purpose for an indefinite period withoiii'et'erence to the wear of the drill, which' wonld'not be the case if thedrill-rod andeut-tingiiead were all in one piece, because as-soon as the cutter rod would have to be thrown away ami rasted. The arrangement ot' holes'or intornalfpnssages here described iii the enticing-head eu l ablos the cuttings ordrillingsto pass upward through the center as -well as on the ojtside oi the cutting-head, and the combination of to lift the cuttings which are passed up from theoeiiter of the cutting-head ,as Well as from tbe'outside. y

it;l will sometimes be found desirable to slightly incline the cross hole or passage d up"- ward from the place where it .intersects the hole c toward its two ends to facilitate the dis- It, is obvious that iii the construction which have shown the spiral may be readily removed` or replaced, it' desired, and that; should the ends of the rib break ata, the shoulder formed by the head would support the spiral rib and prevent it coming oli'.

I claiin v l. The combination, with a drill-rod, of a separate spiral ribf to carry up the borings,

the rib may be securely held iii position, siibstaiitially as described. Y

terior groove or grooves, e., central passage, o, extending down to the cutting-edge, and the 5. The drill-liead B, provided with theeir transverse passage d, substantially as and forY the purpose specified.

c and d, with the spiral on the drilbrod, substantially as described( 6. The combination of the interior passages,

7. The combinatioiiof the eaterior'groore or grooves., e, with 1flic-spiral outho drill-rod,--`

substantially as described. y

8. The combination of the rod A, liaviii'ge spiral groove, and the spiral rib, with the re- `movable head B, provided with a shoulder to,

hold the rib ou the rod, substantially andeJe scribed.

l lHENRY F. PARSONS.

Witnesses:

DANIEL H. DinsooLL,

charge of the drihiiiiigs through it.'

WILLiiiiiirv C. Tmsr, Jr. 

